I would go down there in person...not call. Phone calls are obviously not working. A personal appearance might be a little more intimidating. I wouldnt go in kicking and screaming but i would definately have a bit of an attitude. Ask for the manager/owner. Ask him to call the wheel company right now and find out whats going on. Get the number for the company yourself and you call them. Tell them your very disatisfied with there service. Pretty much just make a whole big stink. Maybe it'll get the ball rolling a little faster.

If you annoy the ***** out of the bike store, there gonna annoy the ***** out of the wheel company, whos gonna annoy the ***** out of the guy putting them together.

Its just how you gotta get things done sometimes.